A free app for iPhone, by Vladimir Poriadnikov.
100 Doors Hidden Objects is an escape game with many different levels and puzzles, which you need to solve. In each level you will have to find hidden objects in order to escape the room.
The object you need to find in each level is always the same, but the room and the path you have to take to get out of it will change.
You will have to think hard and find hidden objects that will help you get out of the rooms.
If you want to know more about 100 Doors, you can find its website. There you can also download a free app that will give you more information about it.